Diabetic neuropathy is the most frequent peripheral neuropathy in the western world and includes different forms of neuropathy, the most common of which is diabetic polyneuropathy.
The anatomico-pathological picture of diabetic peripheral neuropathy consists in a focal or widespread non-specific loss of fibers, with demyelination associated with structural or endoneuronal abnormalities of the connective tissue or small vessels.
Various metabolic abnormalities and biochemical changes have been documented both in experimental models of diabetes and in diabetic patients, including an increase in glucose metabolism and a reduction in myoinositol.
The characteristic symptoms of diabetic polyneuropathy include the presence of burning or lancinating pain accompanied by clinical signs of symmetrical impairment of sensitivity, motility, and/or deep tendon reflexes, such symptoms being predominant in the distal segments of the lower limbs.
Diabetic peripheral neuropathy is caused by hyperglycaemia, and metabolic imbalance secondary to hyperglycaemia and ischaemia of the vasa nervorum are the best known pathogenetic mechanisms.
Many variables may speed up or reduce the times when the characteristic symptoms of diabetic peripheral neuropathy in general, and painful peripheral neuropathy in particular, set in; for example, good metabolic control of blood serum glucose levels can certainly delay the onset of these symptoms.
The use of acetyl L-carnitine for the prevention of painful peripheral neuropathy in patients suffering from type 2 diabetes has never been previously described.
In the literature one can find numerous publications that seek to demonstrate or clarify the therapeutic role of acetyl L-carnitine in the treatment of a number of symptoms, including neuropathic pain, in the course of diabetic neuropathy, but these publications do not claim or suggest that acetyl L-carnitine is a useful compound for the prevention of painful peripheral neuropathy in patients suffering from type 2 diabetes.
In Diabetes Care, 2005; Jan.; 28(1): 89-94 it is reported that treatment with ALC is useful for relieving the pain symptoms and for regenerating nerve fibers, in patients suffering from stabilized diabetic neuropathy.
In “Giornale Italiano di Diabetologia, 1998, V. 18, 30-31” the use of acetyl L-carnitine is described for the treatment of neuropathic pain in patients suffering from sensorimotor polyneuropathy.
In Drugs in Research and Development 2002, Vol 3 (4), pp 223-31, the use of acetyl L-carnitine is described for the treatment of neuropathic pain in patients with diabetic neuropathy.
In Diabetologia 1995, VOL/ISS/PG. 38/1 (123) the use of acetyl L-carnitine is described for the treatment of neuropathic pain in patients suffering from diabetic neuropathy.
In “IL GIORNALE DEI CONGRESSI MEDICI, 5, 14-19, 1993” the use of acetyl L-carnitine is described for the treatment of neuropathic pain in patients suffering from diabetic neuropathy on treatment with insulin or oral antidiabetic agents.
In J. of the American Diabetes Association June 2002, Vol 51, Supplement 2, the use of acetyl L-carnitine is described for the treatment of neuropathic pain in patients suffering from diabetic neuropathy.
In CONGRESSO NAZIONALE DELLA SOCIETA ITALIANA DI NEUROFISIOLOGIA CLINICA, ABSTR ACTS, PERUGIA 1-4 Jun., 1994, p 98, the use of acetyl L-carnitine is described for the treatment of neuropathic pain in patients suffering from diabetic neuropathy.
In Clin. Drug. Invest, Vol 10 (6), pp 317-22 1995, the use of acetyl L-carnitine is described for the treatment of neuropathic pain in patients suffering from diabetic neuropathy.
In Int. J. Clin. Pharm. Res. XV(1):9-15; 995, the use of acetyl L-carnitine is described for the treatment of pain in patients suffering from diabetic neuropathy.
In Journal of the Neurological Sciences, 1997, Suppl. to Vol 150 it is reported that acetyl L-carnitine improves nerve conduction velocity in diabetic patients suffering from polyneuropathy.
In IX CONGRESSO NAZIONALE SOCIETA ITALIANA DI FARMACOLOGIA CLINICA; II CONGRESS MEDITERRANEAN SOCIETY CLINICAL PHARMACOLOGY “THERAPEUTIC ADVANCES AND NEW HEALTH PROBLEMS”, VENICE, Oct. 8-10, 1991 ABS, the effect of acetyl L-carnitine treatment on 500 patients suffering from peripheral neuropathy of various different origins is described.
In Drugs 1997 September: 54 (3) 414-421 it is reported that acetyl L-carnitine improves nerve conduction velocity in diabetic patients suffering from neuropathy.
U.S. Pat. No. 4,751,242 describes the use of acetyl L-carnitine for the treatment of neuropathic pain in patients with peripheral neuropathy of various origins, including diabetic peripheral neuropathy.
WO 02 096409 refers to the use of acetyl L-carnitine for the preparation of a medicament with “pre-emptive-type” analgesic activity. What is meant by “pre-emptive” analgesia is a therapeutic strategy that involves the early administration of a substance, in relation to the painful event, capable of blocking the entry of the pain stimulus into the central nervous system, thus preventing the facilitating response evoked by the nociceptive impulse to the spinal cord. The efficacy of a “pre-emptive” analgesic drug according to the description in WO 02 096409 depends not only on the time treatment is initiated in relation to the painful event but also on the effective ability of the drug to prevent alterations of central pain sensitization mechanisms.
WO 02 096409, as an example of preventive pain therapy, indicates the prevention of pain that occurs after a surgical operation.
In these studies, there is never any description or suggestion of the use of ALC for the prevention of painful peripheral neuropathy in patients suffering from type 2 diabetes.
In the medical field no drugs are known which are useful for the prevention of painful peripheral neuropathy in patients suffering from type 2 diabetes.